Church Creek Flood Storage and Resiliency Project

Charleston, South Carolina

The city of Charleston is establishing land use programs that navigate rising sea levels, protect historic buildings, and answer to a high demand for housing. After a 1,000-year flood event in 2015 and a unique opportunity to collaborate with international resilience experts, the Church Creek Flood Storage and Resiliency Project was designed to leverage bought-out parcels to deliver green infrastructure and mitigate future flooding, while creating an ecological park that will offer a new amenity to residents.

 

The Church Creek Basin drains nearly 5,000 acres along the Ashley River and is home to dense residential neighborhoods. In 2015, a 1,000-year flood drenched the area, and the city of Charleston initiated a FEMA-funded buyout of almost 50 homeowners in Bridge Pointe neighborhood, within the Church Creek Basin, which has repeatedly flooded since development of the area boomed in the mid-1970s.  

Because of settlement patterns, land use, and discharge needs in the area, the city of Charleston embarked on the Church Creek Flood Storage and Resiliency Project “to lower flood risk and enhance post-event resiliency while ensuring the vitality and viability of the area.”   

The project is the product of a larger planning initiative, called the Dutch Dialogues, that started in 2017 to arm the city with innovative strategies and tools to combat rising waters and flooding in the Lowcountry. City government leaders obtained support for this project, which would harness insight from thought leaders from the Netherlands and other international experts, through an initiative started by the Dutch Embassy and funded by the Historic Charleston Foundation, the city of Charleston, and other local partners. Through this collaborative effort with the city and these global experts in planning, stormwater management, and climate resilience, the initiative established a city vision based on a new approach to thinking about the interconnectedness of water, land, and people, and their benefits to one another.  

Matt Fountain, the director of stormwater management for Charleston, called this collaborative process the “Dutch approach.” Fountain supervises a large part of the floodplain buyouts in the Bridge Pointe neighborhood, which includes 32 condominiums and nine townhouses that are all contiguous.  

Five-and-a-half years after the receipt of the FEMA Flood Mitigation grant, Fountain is overseeing the construction of public space on the bought-out sites, whose impact may ripple through property values throughout the Church Creek Basin. The new five-acre, $1 million public space will include recreational and water management features and is being funded by the city’s drainage fund and two National Fish and Wildlife Foundation (NFWF) grants.   

The project team, including conservation planning, ecological restoration, and design firm Biohabitats, engineers Weston & Sampson, landscape architects Surculus, wetlands habitat conservation and mitigation firm Wildlands, and public benefit conservation corporation Resilient Land Matters, are working on establishing a forest and wetland restoration projects on a total 20 acres of the basin. Construction is likely to begin by 2022. The Church Creek Basin resilience project will also include an ecological park for residents and tourists.   

The project embodies the design approach that came from the Dutch Dialogues, in that the city is using the water to its advantage. “We’re trying to convert this into some kind of passive recreation space, with water storage and space for native habitat including bald eagles,” Fountain said.  

With additional NFWF grants for design and management of the park site totaling $1.625 million, city leaders have been trying to upend traditional thinking about development. Rather than seeking an “ever-bigger pipe” to discharge inescapable floods, Fountain’s team aims to create parks and drainage sites that fortify the waterfront city’s natural appeal. As a result of this focus on waterlines and topography, Fountain says, “what would be a secondary benefit for someone else’s project is a primary benefit for us.” The grant is being used to construct rain gardens, protected wetlands, and other green infrastructure improvements on the lots where the homes were bought out and demolished in 2019. 

His team also aims to increase resident knowledge about how to manage water on site. A group called the Ashley-Cooper Consortium has joined the city in running workshops to help residents perform their own “green infrastructure” maintenance with cisterns and other fixes. Faith leaders have also done much outreach on this initiative to homeowners associations, Fountain said. “We talk a lot at the city about trying to make this one project that does lots and lots of things.” Using this program of work to educate the community on green infrastructure benefits and maintenance is a co-benefit to the city.  

The Church Creek Flood Storage and Resiliency Project plan hinges on recalculating the site’s value—not just for salability, but for floodwater storage. In taking land off the market, though, the team also recognizes the risk of upward pressure on prices in neighborhoods and on traffic throughout the city. “Development pressure is intense, and affordability is fragile,” says Fountain. He estimates the city will spend between $12 million and $15 million on property buyouts and the retrofits of these properties in flood storage. This includes the acquisition of between 50 and 60 moderate-income housing units in a city of 150,000 people. With those economics, storage value needs to translate to more traditional forms of value while offering multiple benefits.  

Exploring the frontier means new collaboration across communities and government agencies. The collaboration plays out in new policy, like the city’s Stormwater Design Standards Manual, which reflects debate among homeowners associations, engineers, scientists, and others who treasure Charleston for its kinship with the coast.  

“We see projects that emphasize rebuilding with resiliency,” Fountain says, “as a leveraged opportunity to send people back out into the market.”   

The Charleston Stormwater Design Standards Manual, updated in 2020, has key principles that include mimicking natural systems, designing for larger precipitation rates and future sea-level rise projections, incentivizing green infrastructure, and adding special rules for flood-prone areas. The manual translates stormwater design strategies into criteria required for permitting. For the city’s own projects, they must also score adequately on cost/benefit analysis, biodiversity, operations, and physical safety in a new stormwater project prioritization system the city developed with infrastructure consulting firm AECOM.  

Takeaways: 

Think beyond typical jurisdictions and borders for creating funding sources and innovative collaboration opportunitiesThe city of Charleston found a key funding partner in NFWF, which typically focuses on national parks but also offers grant programs with an urban/suburban environmental focus. City planners also gained tremendous value from Dutch Dialogues, a program which offered international insight and expertise and brought together a number of local stakeholders in the process. 

Take a “living with water” approach. Unlike other cities explored during research, Charleston did not solely predicate its Church Creek Basin buyouts on the impetus to stop repeated flood-damage claims. The Church Creek resilience project aimed to recharacterize a neighborhood in harm’s way as something harmonious with rising seas by changing land use patterns and investing in green infrastructure that would manage future flooding.  

Derive value from design. The Dutch Dialogues and stormwater guidelines have found their way into city contracts, documents, and formal policy. The Stormwater Design Standards Manual is used on all new private and public development and redevelopment projects in the city, while the design principles created the metrics for the city’s new quadruple-bottom-line stormwater project prioritization system.